This invention is concerned with video control systems and more particularly is concerned with such systems using video recording storing a video program.
It is desirable to provide a video control system which decrypts encrypted broadcasts or recorded copies of video material such that the subsequent viewing is controlled. This allows the owner to either forbid viewing, or collect revenue at his or her discretion.
In the prior art, a software distribution system is known wherein a computer program is downloaded once, followed by an access key to allow use of it on each subsequent use. This system uses a dynamic key that constantly changes, and is directly related to an user's decoder box, both by ID and an internal dynamic counter.
Also known is a video system that autonomously controls the viewing of a recording for either 24 hours or once only. It does not have the power of control desired.